Cruciferous vegetables have been in the news recently thanks to their cancer-fighting properties.
These vegetables are rich in phytochemicals, vitamins, minerals and fiber that provide many beneficial effects on the body like anti-inflammatory, antioxidant, antibacterial, antifungal, neuroprotective, hypoglycaemic and lipid-lowering effects.
Experts recommend that we eat several servings of these vegetables like broccoli, kale, and cabbage, to enjoy their health benefits.
What are cruciferous vegetables?
Cruciferous vegetables belong to the Brassica genus, which is why they are also called brassicas. These vegetables are named after the Latin word Cruciferae, which means cross-bearing because the blossoms of these plants resemble a cross.
Though they are native to Europe, the Mediterranean and the temperate regions of Asia, these vegetables are now cultivated all around the world.
Cruciferous vegetables include –
- Bok choy
- Brussels sprouts
- Collard greens
- Mustard greens
These vegetables are a rich source of fiber, vitamin C, K, and E, folate, minerals, carotenoids, and glucosinolates. Glucosinolates are the sulfur compounds that give the bitter taste and pungent smell to these vegetables.
Health benefits of cruciferous vegetables
Cruciferous vegetables offer many health-promoting benefits as they are rich in many essential nutrients. Several studies have shown that these dark leafy vegetables are amongst the highest in nutrient density.
1. Lower risk of cancer
One of the biggest reasons to include more cruciferous vegetables in your diet is that they help to lower the risk of cancer. These vegetables contain glucosinolate, which degrades into isothiocyanates, which fight cancer in numerous ways.
These antioxidants detoxify anti-carcinogenic compounds before they can do any damage. They also alter the cell-signaling pathway that can lead to cancerous cell proliferation and impact epigenetic regulation and lower inflammation (1, 2).
Sulforaphane, which is produced by the hydrolytic conversion of glucoraphanin after ingestion of cruciferous vegetables, possesses the capacity to intervene in multistage carcinogenesis by regulation of critical cellular mechanisms. It is known to be selectively toxic to malignant cells (3).
Over the years, several studies have linked cruciferous vegetable to lower rates of cancer and higher rates of cancer survival. A review of 7 cohort studies and 87 case-controlled studies showed an inverse relationship between the consumption of cabbage, cauliflower, broccoli and the risk of stomach, lung, colon and rectal cancer (4).
2. Lower risk of heart disease
According to a study published in the American Journal of Clinical Nutrition, an increase in consumption of vegetables, mainly cruciferous vegetables, and fruits promotes cardiovascular health and overall longevity (5).
These vegetables are also rich in fiber and antioxidants which are beneficial for heart health.
Cruciferous vegetables possess cholesterol-lowering properties which help lower the risk of heart disease. These vegetables contain compounds that bind to bile acids, which helps in cholesterol control.
Bile is used by the body to absorb and digest the fats that we eat. When compound in cruciferous vegetables binds these bile acids, they are eliminated from the body.
The body then uses its cholesterol stores to replace these bile acids, which in turn helps lower cholesterol levels. Steam cooked collard greens, kale, mustard greens, broccoli, green bell pepper, and cabbage are the best for improving cardiovascular health (6).
According to a 2009 study from Iran, researchers gave rats an extract containing 2% of broccoli sprouts for ten days.
The results showed that this dietary treatment with broccoli sprouts could actively protect the heart against oxidative stress and cell death which was caused by ischemia-reperfusion.
Chronic inflammation has been linked to many diseases including heart disease, cancer, diabetes, and arthritis. Several studies have shown that cruciferous vegetables have a positive effect on biological factors that signal inflammation in the body.
During a 2014 study, researchers observed that a higher intake of cruciferous vegetables is associated with up to a 25 percent reduction in the markers of inflammation in 1005 middle-aged Chinese women (7).
The anti-inflammatory benefits of these vegetables also help reduce the risk of conditions like rheumatoid arthritis, ulcerative colitis, and asthma.
One of the most common hormonal imbalances in women is estrogen dominance. Too much estrogen can lead to symptoms like bloating, irregular menstrual periods, decreased sex drive and headaches.
Cruciferous vegetables are also known to contain a compound known as indole-3-carbinol that helps promote the production of less potent forms of estrogen (8).
Consuming more cruciferous vegetables helps regulate estrogen levels to prevent adverse side effects.
5. Weight loss
Cruciferous vegetables are low in calories and carbohydrates and high in fiber, which makes them the perfect food for weight loss. These vegetables increase the volume of your meals without increasing the calories.
According to a study, each serving of cruciferous vegetables was associated with .68 pounds of weight loss over two years (9).
Another study published in The Journal of Biochemistry found that the compound indole-3-carbinol present in cruciferous vegetables helped prevent obesity in mice that were fed a high-fat diet.
This compound helps decrease inflammation, reduces the formation of fat cells and increases the number of calories burned.
6. Reduce diabetes risk
British researchers have found that sulforaphane, a compound present in cruciferous vegetables, can help protect the body’s circulatory system from oxidative stress, which is especially beneficial for those with diabetes.
These vegetables are also rich in dietary fiber, which slows down the absorption of sugar in the bloodstream and this helps prevent spikes and crashes in blood sugar.
According to a 2016 study from China, higher consumption of cruciferous vegetables significantly decreases the risk of type 2 diabetes (10).
7. Improve bone health
Cruciferous vegetables are rich in vitamin C, vitamin K, calcium, and magnesium. All these nutrients are needed by the body to keep bones healthy.
Cruciferous vegetables are also alkalizing, so they help balance out the acidic food like meats, dairy, and sugar. Acidic foods tend to leach calcium from the bones and make them weak.
8. Depression relief
Cruciferous vegetables contain sulforaphane which may provide relief from depression. According to a 2016 study, when sulforaphane was administered to chronically stressed mice, it significantly reversed anxiety-like behavior (11).
Inflammation can lead to depression and the anti-inflammatory properties of cruciferous vegetables prevent depression.
9. Help reduce pain
Cruciferous vegetables contain sulforaphane which can be very useful in pain management. According to a 2000 study, 12 female patients with fibromyalgia were given 500 mg of a blend of 100 mg ascorbigen and 400 mg broccoli powder per day for one month. The results showed reduced sensitivity to pain and an improvement in the quality of like (12).
Another study tested the antinociceptive (pain blocking) effects of broccoli sprout aqueous extract. The results showed that there is evidence of potential activity of broccoli sprout aqueous extract in pain therapy (13).
Side effects of cruciferous vegetables
Though cruciferous vegetables have many benefits, they can also cause some side effects if you eat them in large quantities.
The fiber found in cruciferous vegetables undergoes fermentation in the large intestine which can lead to digestive issues. These foods are more difficult for the body to absorb.
When they move to the large intestine, they cause the intestinal walls to swell, which leaves you feeling bloated.
Cruciferous vegetables can also lead to thyroid problems. When they are eaten raw, cruciferous vegetables release goitrogens in the intestines during the digestive process, which increases the need for iodine and can damage the thyroid gland.
People with thyroid issues should limit their intake of these vegetables. Though generally considered safe, some people may be allergic to specific cruciferous vegetables. The symptoms of this allergic reaction can include rashes, swelling, and hives.
Recommended intake and tips to cook
- According to researchers, you should consume at least five serving of these healthy vegetables per week.
- The most nutrient-dense part of cruciferous vegetables is their florets.
- When buying fresh broccoli, choose firm florets with purple, dark green or bluish hue. They contain more vitamin C and beta-carotene.
- The darker and more colorful the vegetables are the higher in their nutrient content.
- Don’t overcook cruciferous vegetables as they can produce a strong sulfur odor which can be quite unappealing.
- Limp, bendable broccoli which is yellow on top is not fresh and should be avoided.
- Add broccoli or cabbage to raw salads to add to its nutrient content.
- Fresh cabbage can be used to make the perfect healthy coleslaw.
- You can also roast broccoli and cauliflower with oil and herbs.
- These super healthy vegetables can also be added to soups, stews, and casseroles.
Cruciferous vegetables belong to the Brassicaceae family. They contain nutrients with anti-cancer properties and are rich in vitamin C, E, K, folate, fiber, and antioxidants.
They are a good source of phytonutrients that help lower inflammation, lower the risk of heart disease and reduce the risk of developing cancer.
So, do not underestimate the many benefits of eating nutrient-rich cruciferous vegetables. Take advantage of this bounty from nature and have at least five serving of these vegetables every week.
Avoid very high amounts of cruciferous vegetables as they may cause digestive problems.